The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
There are a rim brake type and a brake disk type as types of bicycles.
The rim brake type is a type obtaining braking force by contacting a pad on a rim, and there are caliper brake, cantilever brake and V brake.
The brake disk type is a type obtaining braking force by contacting a pad on a rotor connected with a hub body of a bicycle, and there are mechanical and hydraulic pressure types.
The mechanical type brake disk is a type that a caliper in which a brake pad is installed fixes a disk rotor connected with the hub body by pulling a cable, and the hydraulic pressure type is a type that the caliper fixes the disk rotor to obtain braking force by using hydraulic pressure, not by using the cable.
The brake disk includes a brake handle connected with a bicycle handle bar, a brake cable, a brake lever connected with the brake handle by the brake cable, a caliper fixing a disk connected with a hub body shaft of the bicycle by the brake lever to perform braking motion.
Meanwhile, the disk is disposed at outside of the hub body and may be bent according to braking motion by outside shock. The disk may be sharp to cause fatal injury on human body, and a front wheel of the bicycle generates moment in one direction during braking causing instability of steering.